1. Field of the Invention
The present invention relates to a gate apparatus for use in combination with an injection-molding die for injection-molding a resin and, more particularly, to a gate apparatus suitable for molding a relatively thin molding.
2. Description of the Prior Art
A hot-runner system using a down gate to inject a resin through an upper portion of an injection-molding die into a cavity has been generally used. However, when such a down gate mark is used, a gate is formed on the upper surface of the molding to spoil the appearance of the molding. If a cross gate is formed in the side portion of an injection-molding die, a cold runner is necessary and the runner cannot be kept hot. A known gate apparatus which has been used to obviate such troubles is provided with a cross gate 13 formed in a cylindrical down gate 12 formed in a female die 11 as shown in FIG. 5. The diameter D of the cylindrical down gate 12 is as large as about 30 mm. Therefore, if the injection-molding die is a multiple-cavity die, the cavities need to be formed inevitably at large intervals. Since the height h of the cross gate 13 from the bottom surface of the cylindrical down gate 12 is, for example, as large as about 10 mm, the lower limit of the height H of the molding, which is dependent on the distance between the lower surface, i.e., the lower surface corresponding to the parting line, of the female die 11 and the bottom surface of the cavity of the female die 11, is relatively large. Accordingly, it is difficult to mold a relatively thin molding, such as the half case of a tape cassette, by using such an injection-molding die.